linux-wandboard

netxen: hold tx lock while sending firmware commands

Some firmware commands like mac address addition/deletion are sent
on the transmit ring. So need to hold the tx lock before touching
tx producer/consumer indices.

Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>